London launches hi-tech desalination plant to stave off drought, and it will be powered by a renewable fuel found in abundance in the city -- fish fry oil.

Many of you will be surprised to learn that dark and rainy London is in the midst of a serious drought, and now the city is hoping to hedge dwindling water supplies with a new desalination plant.

Initially fought by environmentalists in England, the Thames Gateway Water Treatment Works was officially opened this month in London's Beckton district, along with assurances that it will be the most energy-efficient to date. The plant will use tidal river water with an 85 percent conversion to drinking water and it will run on a cheap and renewable fuel found in abundance in London — fish fry oil.

The plant will capture water at the confluence of the river and the sea. This greatly reduces the amount of energy required to extract salts thus making the water potable. Desalination plants are typically immense energy hogs, which caused climate sensitive Londoners to react negatively when the plant was announced three years ago.

So the city got creative with the plant and created a program to collect fish fry oil from around the city to power the plant. It's unlikely the waste oil will be sufficient to keep the plant running full tilt, but it will help reduce the carbon impact of such a massive water treatment facility.

At its peak the plant would be able to deliver 140 million liters of water — enough to supply 400,000 homes. Record water shortages in the summers of 2005 and 2006, which many attribute to climate change, shocked the city into action. And despite its environmental impact on the city, many Londoners are relieved that clean drinking water is now at the ready.